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Thank you both for your comments.

 

My understanding (in layman's terms) is that we have all this 'depleted uranium' waste from the once-through system, but some Gen 3 (MOX?) reactors can 'breed' fuel from this waste, creating vastly more baseload power from existing waste.

 

That is, America's waste becomes 'fuel' that could run America for the next 500 years. Reprocessing doesn't burn it all up, but apparently will reduce it 90%. The 10% that is left is highly radioactive but for a shorter period, say 300 to 500 years. Not only that, but when all the normally economic highly concentrated ore bodies of uranium and thorium on earth have been mined, breeding fuel makes even the background uranium from seawater or the earth's crust possible! The ERoEI is apparently so high with breeding that there is still enough energy left over to extract uranium even at tiny parts-per-million from normal granite!

 

So imagine some distant day when all the uranium on earth has been mined, and then this advanced future civilisation could, if needed, just start on one side of a continent mining down to about 4 or 5 km depths, extracting all useful minerals and energy products, and putting it back and reshaping the world as they see fit. This post really caught my attention.

 

What is the size of the resource? Let's assume that only the portion of continental crust currently under dry land is exploited for its uranium and thorium content, to a depth of roughly four kilometres (the deepest mine currently operating is the TauTona mine in Carletonville, South Africa at 3,900m, and the Kola Superdeep Borehole in Russia is 12,262m). This represents a reserve of 20 trillion tonnes of fertile and fissile fuel, capable of powering our 100TW civilisation for 200 million years. This is the span of time separating us from the dawn of the Jurassic Period, when the supercontinent Pangaea was starting to break apart into Laurasia and Gondwana. Dinosaurs were just beginning to make their mark on the world, and the allosaurus, stegosaurus and diplodocus were yet to evolve.

 

(This is only if this future civilisation haven't invented fusion, super-batteries that can store wind & solar power super-cheap, or if they don't have self-replicating space robots mining the asteroid belts, Jupiter, etc and building space solar power so we won't even NEED fission)

 

This seemed so ideal to me that I was jumping for joy when I found out about it! However, then the complication.

 

A 'portion' (which I'm hoping is tiny) of the 10% waste left over is still radioactive forever... for 100 thousand years, and some Fission Products are radioactive for millions....

 

So my question is:

 

Can they separate out the shorter and longer lived products for different storage processes? Is it even worth doing it, or would they just dump the whole 10% into vitrified balls and dump it into subduction zones?

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Most of the links given for that search on blingo.com can be traced back to NextEnergyNews.com. One however is of interest and I quote from a letter, suppose to be from Toshiba's Corporate Communicat

Think of it this way: Nuclear Power is the second-worst way in the world to generate electricity. The worst way: ANY fossil-fired plant. With the advent of computerized controls, all manner of ren

Let us not forget the very important future role of thorium---see below---from Wiki, so take with a grain of salt. Where you know facts are incorrect, then correct in Wiki..   == Thorium as a nuclear

Is nuclear power the key to the energy needs of the future? New nuclear power plant designs with less shorter lived waste and small sizes may revolutionize the nuclear power idea. Hydrogen production needs intense power sources to supply the hydrogen necessary for a hydrogen economy and electricity for every one needs to be reliable and not Dependant on the weather or on manufacturing that leaks huge amounts of chemical pollution into the environment and depends of cheap labor from foreign countries where people are used up to profit their country. Nuclear can be the answer. Here two examples of the new face of nuclear energy.

 

 

Sustainable Nuclear Energy Moves A Step Closer

 

 

Toshiba Builds 100x Smaller Micro Nuclear Reactor

 

I found this something to read: Fushion Fission hybrid

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Well, I know his argument is not correct that using nuclear power will raise the cost of generating electric energy, and thus raise the cost of goods to society, because France uses nuclear power for ~ 60% of its national electric energy production, and the last time I was in France, costs were no more than in many areas of USA (say NJ for example). Also, even a small amount of money put into research for fusion reactors should result in major discoveries and eliminate concern over storage of radioactive waste. Of course, nuclear war also a concern--but you know--it is too late. It would be like the Romans complaining that war is just not fair anymore if some culture had invented the rifle in 150 BC--ban the rifle the Romans would claim--see how expensive it is. Nuclear power, especially for space travel is the future of mankind, and the sooner we reach the end point, the better. Put a tax on burning coal and then see how quickly the argument that nuclear power is more expensive disappears--better yet--just treat the toxic coal fly ash waste as a haz-waste and cost of nuclear energy will look like best thing since slice bread overnight.

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Let us not forget the very important future role of thorium---see below---from Wiki, so take with a grain of salt. Where you know facts are incorrect, then correct in Wiki..

 

==

Thorium as a nuclear fuel

 

Thorium, as well as uranium and plutonium, can be used as fuel in a nuclear reactor. A thorium fuel cycle offers several potential advantages over a uranium fuel cycle including much greater abundance on Earth, superior physical and nuclear properties of the fuel, enhanced proliferation resistance, and reduced nuclear waste production. Nobel laureate Carlo Rubbia at CERN (European Organization for Nuclear Research), has worked on developing the use of thorium as a cheap, clean and safe alternative to uranium in reactors. Rubbia states that a ton of thorium can produce as much energy as 200 tons of uranium, or 3,500,000 tonnes of coal.[13]

 

One of the early pioneers of the technology was U.S. physicist Alvin Weinberg at Oak Ridge National Laboratory in Tennessee, who helped develop a working nuclear plant using liquid fuel in the 1960s. For many reasons, including a lack of need for high-pressure water containment domes, thorium-fluoride reactors can be smaller and less expensive to build and run than uranium reactors.[13]

[edit] Key benefits

 

According to Australian science writer Tim Dean, "thorium promises what uranium never delivered: abundant, safe and clean energy - and a way to burn up old radioactive waste."[14] With a thorium nuclear reactor, Dean stresses a number of added benefits: there is no possibility of a meltdown, it generates power inexpensively, it does not produce weapons-grade by-products, and will burn up existing high-level waste as well as nuclear weapon stockpiles.[14]

 

Ambrose Evans-Pritchard, of the British Telegraph daily, suggests that "Obama could kill fossil fuels overnight with a nuclear dash for thorium." He advocates setting up a new Manhattan Project, as the U.S. did to rapidly develop nuclear weapons during World War II, in order to "marshal America’s vast scientific and strategic resources" in developing thorium reactors. It could put "an end to our dependence on fossil fuels within three to five years," he stresses.[13]

 

The Thorium Energy Alliance (TEA), an educational advocacy organization, emphasizes that "there is enough thorium in the United States alone to power the country at its current energy level for over 1,000 years." They also note that a thorium power plant can be "designed to tap right in at the source of a current coal or uranium plant," without the need for laying a new grid.[15] In addition, reducing coal as an energy source, according to science expert Lester R. Brown, of The Earth Policy Institute in Washington DC, would reduce deaths, certain diseases, and medical costs. He estimates that air pollution from coal-fired power plants causes 23,600 U.S. deaths per year, and is also responsible for 554,000 asthma attacks, 16,200 cases of chronic bronchitis, and 38,200 non-fatal heart attacks annually. His institute states that the "U.S. health bill from coal use could be up to $160 billion annually."[16]

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Nuclear waste recycling

UREX, a solvent extraction process using the extractant tributyl phosphate (TBP) similar to the well known PUREX process, can then be used to extract uranium that is sufficiently decontaminated to permit its disposal as low level waste. Batch tests have shown 99.999% recovery of uranium with contamination from technetium, neptunium, and plutonium many orders of magnitude lower than necessary for classification as Class C waste.

 

Government to Study Nuclear Waste Recycling

For economic and national security reasons, the United States does not currently recycle used nuclear fuel. After its use once in the reactor, companies remove it for ultimate disposal in a repository. This “once-through” fuel use is called an "open" fuel cycle. The recycling and reuse of nuclear fuel is called a "closed" fuel cycle. This approach would capture the vast amount of energy still remaining in used nuclear fuel.

 

Converting Used Fuel Into New Fuel

Through recycling, the separated uranium would become new fuel for commercial nuclear power plants. The long-lived radioactive elements, including plutonium, become fuel that could be used in advanced reactors that would be developed commercially as part of the research and development program.

 

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Ambrose Evans-Pritchard, of the British Telegraph daily, suggests that "Obama could kill fossil fuels overnight with a nuclear dash for thorium." He advocates setting up a new Manhattan Project, as the U.S. did to rapidly develop nuclear weapons during World War II, in order to "marshal America’s vast scientific and strategic resources" in developing thorium reactors. It could put "an end to our dependence on fossil fuels within three to five years," he stresses.[13]

 

Wishful thinking from Wiki, IMO, but would significantly better the USA's position and lessen dependence on fossil fuels. I've come to realize it's not so easy to replace fossil fuels just yet... We've not made any serious moves and business continues as usual as the clock keeps ticking. Thorium needs to get on the national agenda soon and fast.

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I just wanted to reply to something Amory Lovins wrote back on the first page of this thread.

 

What nuclear would do is displace coal, our most abundant domestic fuel. And this sounds good for climate, but actually, expanding nuclear makes climate change worse, for a very simple reason. Nuclear is incredibly expensive. The costs have just stood up on end lately. Wall Street Journal recently reported that they’re about two to four times the cost that the industry was talking about just a year ago. And the result of that is that if you buy more nuclear plants, you’re going to get about two to ten times less climate solution per dollar, and you’ll get it about twenty to forty times slower, than if you buy instead the cheaper, faster stuff that is walloping nuclear and coal and gas, all kinds of central plans, in the marketplace. And those competitors are efficient use of electricity and what’s called micropower, which is both renewables, except big hydro, and making electricity and heat together, in fact, recent buildings, which takes about half of the money, fuel and carbon of making them separately, as we normally do.

 

My understanding is that much nuclear power in the USA is constrained by single-build costs. It's like reinventing the wheel every time you guys decide to build one! All those contractors have to be brought in, systems set up, and a bunch of engineers brought in as the local construction guys get together and think, "What, NUCLEAR? Wow!" and scratch their heads and try to listen to the new bosses on how they're to do stuff the nuclear way.

 

Amory hasn't considered that nuclear power plants are in development that one day may come off the assembly line. GenIV reactors are going to be modular. That is, the plan is to build them on the production line. Huge modular parts will be trucked to the site, and assembled their like giant lego. GenIV reactor prototypes are one step closer with this announcement.

 

http://www.genewscenter.com/Press-Releases/GE-Hitachi-Nuclear-Energy-and-Savannah-River-Nuclear-Solutions-Sign-Agreement-on-Small-Modular-Reactor-Technology-2c20.aspx

 

And what's the incentive for not just agreeing to build 1 or 2 plants but build a FACTORY system for nuclear plants? Simply this: the country that gets this industry going first wins. They'll be able to sell to the rest of the world, once other nations realise the potential. And in the meantime they'll be able to accept the world's nuclear waste and warheads and BURN THEM for energy in these reactors!

 

Personally, I wish Australia would start accepting as much of the world's nuclear waste as we can right now under the pretext that we'll 'store it in our stable geology'. ;)

 

Then when we end up buying the 50 GenIV reactors we need from China, we'll have enough waste (fuel) to run Australia for hundreds of years while STILL being able to mine and sell our uranium to the rest of the world! How good is that? After all, the world's nuclear 'waste' is rumoured to be worth $30 trillion dollars. Why so much? It could run today's modern world for 500 years.

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